Self-service refrigerated display case



March 24, 1964 w. E. URAL 3,125,864

SELF-SERVICE REFRIGERATED DISPLAY CASE Filed Oct. 16, 1962 6 2Sheets-Sheet 1 'O INVENTOR W/L /AM E. URAL m q E March'24, 1964 w. E.URAI. 3,125,864

SELF-SERVICE REFRIGERATED DISPLAY CASE Filed 001'.. 16, 1962 2Sheets-Sheet 2 i: 2 f// ff tzi'. /'/;y Figa' BY @wf/v7 CaSeS.

United States Patent O,F

3,125,864 SELF-SERVICE REFRIGERATED DISPLAY CASE William E. Ural,Yardley, Pa., assigner, by mesne assignments, to The American HardwareCorporation, a corporation lof Connecticut Filed Get. 16, 1962, Ser. No.230,352 Claims. (Cl. 62--256) This invention relates to refrigerateddisplay cases and is directed particularly to display cases which areopen at the front for access to the display space and are arranged sothat refrigerated air will ow downwardly adjacent the access opening orin front of shelves within the display space.

It has been common practice heretofore to provide refrigerated displaycases with a relatively high back wall which may be provided with one ormore vertically spaced shelves and to provide the front of the case withan access opening through which the shelves and display space areaccessible. Such display cases are ordinarily provided with means forcirculating refrigerated air downwardly adjacent the access opening inthe front of the case to a return air duct opening adjacent the loweredge of the access opening.

The air thus circulated is sometimes presented in the form of adownwardly flowing air curtain or barrier which extends from a cold airoutlet adjacent the upper edge of the access opening to an air returnduct having a return air inlet adjacent the lower edge of the accessopening. In other constructions cold air may flow forward from the backWall of the case or downward from the top of the case onto the shelvesand thereafter cascade downward over the front edges of the shelves soas to flow downward adjacent the access opening in the front of thecase. The air then is returned to be recooled and recirculated bypassage to a return air duct having a return air inlet adjacent thelower edge of the front access opening.

When employing either type of air circulation, the downwardly flowingrefrigerated air entrains or induces a downward flow of ambient airadjacent the front access opening. The air thus caused to flow downwardis cooled by the transfer of a portion of its heat to the refrigeratedair and by commingling therewith. As a result, the volume of air whichflows downward toward the return air inlet is increased and generallyexceeds the capacity of the inlet and return air duct. Therefore,substantial volumes of cool or relatively cold air spill forward out ofthe case causing substantial loss in refrigeration and creating anuncomfortably cold condition for the feet and legs of customers in theaisle in front of the case.

In accordance with the present invention, the uncomfortable conditionsthus created are reduced or eliminated and a substantial saving in heatloss and an increase in the efficiency of operation of refrigerateddisplay cases may be attained.

These advantages are preferably attained by providing open front displaycases with one or more added or 'enlarged ducts or passages throughwhich substantially all or the major portion of the cooled air owingdownward toward the lower edge of the access opening may be passed. Aportion of such cooled air may then be refrigerated again and returnedto the display space in a continually recirculating cycle as inconventional front access display However, the other portion orremainder of the cooled air may be directed elsewhere to aid in airconditioning the store, to refrigerate other equipment, to cool acondenser, or it may be utilized in any other manner desired or simplydischarged to some space where it will not be objectionable.

Accordingly, the principal objects of the present inven 3,125,864Patented Mar. 24, 1964 ICC tion are to prevent objectionable spillingover of cooled air adjacent the lower edge of an access opening in thefront of a refrigerated display case, to assure more elfectiveutilization of refrigeration in front opening display cases, and tocontrol the flow of ambient air which is cooled by refrigerated airflowing downward adjacent the front access opening in a refrigerateddisplay case.

These and other objects and features of the present invention willappear from the following description thereof wherein reference is madeto the gures of the accompanying drawings.

In the drawings:

FIG. 1 is a vertical sectional View through a typical form ofrefrigerated display case embodying the present invention;

F IG. 2 is a horizontal sectional view through the display case shown inFIG. 1;

FIGS. 3, 4 and 5 are sectional views illustrating various alternativeembodiments of the present invention.

In that form of the invention chosen for purposes of illustration inFIGS. 1 and 2, the display case has a base or insulated bottom, avertical rear wall 4 and a top or hood 6. The ends 8 of the case slopeforward from the ends of the hood 6 to lower front wall 10 which denesthe lower edge of an access opening 12 in the front of the case. Shelves14 are arranged in vertically spaced relation Within the display space16 and in position to be accessible through the front opening 12 of thecase.

The bottom of the display space 16 is defined by a lower floor or pan 18which is spaced from the base 2 of the case so as to provide arefrigerating space 20 within which is located the evaporator 22 of arefrigerating unit. A second evaporator unit 24 is located at the rearof the display space and extends vertically adjacent the rear insulatedwall 4. A blower 26 is positioned between the evaporators 22 and 24 andserves to cause air to be circulated beneath the oor 18 of the displayspace and over the evaporators 22 and 24 so as to be forced upwardthrough the refrigerated air duct 23 to the air discharge spaces 30beneath the shelves 14 and the air discharge space 32 beneath the hood6.

The refrigerated air is thus caused to flow forward and downward overthe articles in the display space 16 and located on the shelves 14. Theair then ows forward to duct means 34 located at the rear of the lowerfront wall 10 of the display case and below the front access opening 12.In so doing, the refrigerated air protects the articles on display fromthe ambient air in front of the case and forms an air curtain or barrier36 of refrigerated air moving downward adjacent the access opening 12.This movement of the air. establishing the air barrier 36 serves toYcause the ambient air adjacent and in front of the access opening 12 togive up heat by conduction to the air of the barrier 36 and also causessome of said air to be entrained and mingle with the air of the barrier36. In this way, an induced stream of the ambient air 38 is createdadjacent the access opening 12 substantially increasing the volume ofthe air owing downward toward the duct means 34 adjacent the lower edgeof the access opening 12.

In a typical embodiment of the invention as shown in FIG. 1, the displaycase may be used for the refrigeration and display of frozen foods. Insuch a case, the refrigerated air issuing from the spaces 30 and 32 tothe display space 16 may be at a temperature of about 10 F.; whereas,the ambient air may be 70 F. The temperature of the air in the barrier36 will then increase as it ows downward by reason of the absorption ofthe ambient air will be lowered until they reach the lower edge of theaccess opening at temperatures of, say +l F. and +40 F. respectively.However, the volume of these combined streams of air will be nearlytwice the volume of the refrigerated air which was discharged into thedisplay space from the spaces 30 and 32 beneath the shelves. As aresult, there would be a tendency for the induced stream of air 3S at atemperature of only about 40 F. to spill out over the lower front wall10 of the display case at the lower edge of the access opening 12. It isthe spilling of this cold induced air which has heretofore been foundobjectionable because of the loss of refrigeration and the chilling ofchildren and the feet of adults or the legs of customers wearing shortsor having no stockings.

In accordance with the present invention, the duct means 34 adjacent thelower front wall of the display case has a greater capacity or crosssection than the duct 28 at the rear of the case through which therefrigerated air from the evaporators 22 and 24 are passed to thedischarge spaces 3,0 and 32 beneath the shelves 14. As a result, all orthe major portion of the air in both of the air streams 36 and 38 isdrawn into the duct means 34 and little, if any, of the chilled airspills over the lower front wall of the case.

As shown in FIG. l, the duct means 34 is preferably divided into twoseparate ducts or passages into which the parallel flowing air streams36 and 3S may be directed. Thus, the duct means 34 may embody arefrigerated air return passage 4) having an inlet opening 42 throughwhich the colder air stream 36 may be returned to the evaporator 2.2 andblower 26. In a similar way, the duct means 34 may embody a chilled airpassage 44 having an inlet opening 46 through which air may ilow to ablower 48. From the blower 48 the chilled air, which may be at atemperature of about 40 F., may be passed to a discharge flue 50 or toany other suitable location where the chilled air may be utilized orwill not be objectionable.

As shown in FIG. 1, the inlet opening 42 of the refrigerated air returnpassage is located below and inward from the inlet opening 46 of thechilled air passage 44. This arrangement of the air inlet openings ofthe passages of the duct means 34 is preferred since the two streams ofair 36 and 38 are generally parallel to each other and essentiallylaminar in character. However, the air inlet openings may be otherwisearranged and the division of the duct means 34 into two separatepassages need not be effected until the laminar streams of air approachthe lower portion of the duct means 34 adjacent the lower front wall 10of the case.

Further, as shown in FIG. 1, the discharge flue 50, through which thechilled air is forced by the blower 48, may extend upwardly adjacent therear wall 4 of the display case to an outlet opening 52 adjacent thehood 6 or the top of the display case. The chilled air is, thus,discharged upwardly toward the ceiling or upper portions of the store orarea where the display case is located so that it will mingle with thewarm air in the store and reduce the temperature thereof. In this way,the chilled ambient air, which would otherwise be spilled out of thecase in an objectionable manner, could be used to reduce the loadimposed on air conditioning equipment employed for cooling the air inthe store or elsewhere.

In the alternative and as shown in FIG. 3, the chilled ambient air frompassage 60 of the duct means may be directed to another display case orarea to be chilled. Thus, the passage 60, through which the chilled airfrom duct means 34 is passed, may be directed to a case 62 which may bea vegetable stand, dairy case, candy display case or other unit whichdoes not require such low refrigeration as does the case in which theevaporators 22 and 24 or other refrigerating means are located. In thisway, the chilled ambient air from one case may be 4 utilized to increasethe eiciency of the system and extend the usefulness thereof to otherequipment.

As further shown in FIG. 4, the chilled ambient air from a passage 72communicating with the duct means 34 may be directed by a blower '71 tothe condenser '73 of the refrigerating unit 7S in a self containedrefrigerated display case so as to increase the e'iciency thereof of therefrigerating unit by transfer of heat from the condenser to the airdirected from the passage 72 to the condenser 73 by the blower '71.

In the further alternative form of the invention illustrated in FIG. 5,the chilled ambient air received from the duct means 34 at the rear ofthe lower front wall 10 of the case is blown over heating elements by ablower 82 and then is discharged through an outlet 84 near the bottom ofthe front wall 10 of the case. The air thus discharged has itstemperature raised suilciently to overcome any objection thereto wherebyneither children nor adults will be chilled by the cooled ambient air.

In each of the forms of the invention described above, the airapproaching the lower edge of the access opening l2 of the display caseis drawn off in a manner to prevent spillage of cooled air from the caseand loss of refrigeration thereby. In fact, if desired, the inletopening through which the chilled ambient air is drawn may be of suchsize or so located as to draw in unchilled ambient air for mixing withthe chilled ambient air to temper or raise the temperature of thechilled ambient air until it is no longer objectionably cold whendischarged from the case.

The present invention obviously may be used in combination with Varioustypes of refrigerated equipment and with display cases maintained attemperatures above those usually employed in the preservation anddisplay of frozen foods, ice cream and the like. It should, therefore,be understood that the particular embodiments of the invention shown inthe drawings and described above are intended to be illustrative onlyand are not intended to limit the scope of the invention.

I claim:

1. A self-service refrigerated display case having a top, a bottom, endmembers and front and back walls eX- tending about a display space, thefront of the case having an access opening therein and the upper edge ofthe front wall being positioned below said access opening, means forcirculating refrigerated air forwardly and downwardly within the displayspace and adjacent said access opening, duct means located adjacent thefront wall of the case in position to receive air moving for- Ywardlyand downwardly adjacent said access opening, re-

frigerating means within said case, means for conducting one portion ofthe air received by said duct means to said refrigerating means forrecirculation through said display space, and means for directinganother portion of the air received by said duct means to the exteriorof said display space.

2. A self-service refrigerated display case having a top, a bottom, endmembers and front and back walls extending about a display space, thefront of the case having an access opening therein and the upper edge ofthe front wall being positioned below said access opening, means forcirculating refrigerated air forwardly and downwardly within the displayspace and adjacent said access opening, duct means located adjacent thefront wall of the case in position to receive air moving forwardly anddownwardly adjacent said access opening, refrigerating means within saidcase, means dividing said duct means into two separate passages, one ofwhich passages serves to deliver air to the exterior of the displayspace, and the other of which passages serves to return air to saidrefrigerating means for recirculation through the display space.

3. The combination as set forth in claim 2 wherein each of said passagesis provided with a blower for moving air therethrough.

4. The combination as set forth in claim 2 wherein each of said passagesis provided with an inlet located near the upper edge of the front wallof the case.

5. The combination as set forth in claim 2 wherein the passage whichserves to return air to said refrigerating means is located rearwardlyof the other passage.

6. A self-service refrigerated display case having a display spacetherein, means for refrigerating air, a passage through which air fromsaid refrigerating means is circulated to said display space, an openingin said display case providing access to said display space, duct meanscommunicating with the display space near an edge of said accessopening, said duct means having a capacity exceeding that of saidpassage, means for circulating a portion of the air received by saidduct means to said refrigerating means and passage for return to saiddisplay space, and means for circulating another portion of the airreceived by said duct means to the exterior of said display space.

7. A self-service refrigerated display case having a display spacetherein, means for refrigerating air, a passage through which air fromsaid refrigerating means is circulated to said display space, an openingin said display case providing access to said display space, duct meanscommunicating with the display space near an edge of said accessopening, said duct means having a capacity exceeding that of saidpassage, means for circulating a portion of the air received by saidduct means to said refrigerating means and passage for return to saiddisplay space, and means for circulating another portion of the airreceived by said duct means upwardly out of the top of the display case.

8. A self-service refrigerated display case having a display spacetherein, means for refrigerating air, a passage through which air fromsaid refrigerating means is circulated to said display space, an openingin said display case providing access to said display space, duct meanscommunicating with the display space near an edge of said accessopening, said duct means having a capacity exceeding that of saidpassage, means for circulating a portion of the air received by saidduct means to said refrigerating means and passage for return to saiddisplay space, and means for circulating another portion of the airreceived by said duct means to another display case.

9. A self-service refrigerated display case having a display spacetherein, means for refrigerating air, a passage through which air fromsaid refrigerating means is circulated to said display space, an openingin said display case providing access to said display space, duct meanscommunicating with the display space near an edge of said accessopening, said duct means having a capacity exceeding that of saidpassage, means for circulating a portion of the air received by saidduct means to said refrigerating means and passage for return to saiddisplay space, and means for circulating another portion of the airreceived by said duct means past a heating device to the exterior of thecase.

10. A self-service refrigerated display case having a display spacetherein, means for refrigerating air, a passage through which air fromsaid refrigerating means is circulated to said display space, an openingin said display case providing access to said display space, duct meanscommunicating with the display space near an edge of said accessopening, said duct means having a capacity exceeding that of saidpassage, means for circulating a portion of the air received by saidduct means to said refrigerating means and passage for return to saiddisplay space, and means for circulating another portion of the airreceived by said duct means to a condenser for said refrigerating meansand thence out of the case.

1l. A self-service refrigerated display case having a top, a bottom, endmembers and front and back walls extending about a display space, thefront of the case having an access opening therein and the upper edge ofthe front wall being positioned below said access opening, blower meansfor circulating refrigerated air forwardly and downwardly witlr'n thedisplay space and adjacent said access opening, duct means located onthe exterior of the display space and having an inlet opening positionedadjacent the lower edge of said access opening and an outlet openinglocated adjacent said front wall of said display case, additional blowermeans for circulating air through said duct means from said inletopening to said outlet opening, and means for raising the temperature ofthe air circulated through said duct means to said outlet opening.

12. In a refrigerated display case having a display space therein withan access opening facing toward the front of the display case and meansfor refrigerating articles located in said display space, a duct havingan outlet opening through which air may be discharged from said casebelow said access opening, and means located adjacent said outletopening for raising the temperature of the air discharged through saidoutlet opening.

13. In a refrigerated display case having a display space therein withan access opening in the front thereof, means for refrigerating andcirculating air through said display space, duct means arranged toreceive a portion of the air circulated through said display space, ablower for circulating said portion of the air circulated through thedisplay space from the display case below said access opening, and meansfor raising the temperature of the air thus discharged from the case toa temperature above that of the air circulated through the displayspace.

14. A refrigerated display case having a display space therein with anaccess opening in the front thereof, means for refrigerating articles insaid display space including refrigerating means, a blower and ductsthrough which air may be circulated to and from said display space andover said refrigerating means, said ducts having an outlet opening nearthe upper portion of said display space and an air return opening nearthe lower portion of said access opening, a second blower, other ductmeans having an outlet opening located below said access opening in thefront of the display space through which air circulated by said secondblower may be discharged from the display case to the area or aisleadjacent the front of said display case, and means for raising thetemperature of the air discharged through the latter outlet opening.

15. A refrigerated display case having a display space therein with anaccess opening in the front thereof, means for refrigerating articles insaid display space including refrigerating means, said refrigeratingmeans having an evaporator and a condenser, a blower and ducts throughwhich air may be circulated to and from said display space and over saidevaporator, said ducts having an outlet opening near the upper portionof said display space and an air return opening near the lower portionof said access opening, a second blower, other duct means having anoutlet opening located below said access opening in the front of thedisplay space through which air circulated by said second blower may bedischarged forwardly from the display space into the area or aisleadjacent the front of the display space, and means including saidcondenser for raising the temperature of the air discharged through thelatter outlet opening.

References Cited in the le of this patent UNITED STATES PATENTS2,066,312 Bales Jan. 5, 1937 2,673,455 Brinkoeter Mar. 30, 19542,706,387 Swanson Apr. 19, 1955 2,911,799 Guyton Nov. 10, 1959

1. A SELF-SERVICE REFRIGERATED DISPLAY CASE HAVING A TOP, A BOTTOM, ENDMEMBERS AND FRONT AND BACK WALLS EXTENDING ABOUT A DISPLAY SPACE, THEFRONT OF THE CASE HAVING AN ACCESS OPENING THEREIN AND THE UPPER EDGE OFTHE FRONT WALL BEING POSITIONED BELOW SAID ACCESS OPENING, MEANS FORCIRCULATING REFRIGERATED AIR FORWARDLY AND DOWNWARDLY WITHIN THE DISPLAYSPACE AND ADJACENT SAID ACCESS OPENING, DUCT MEANS LOCATED ADJACENT THEFRONT WALL OF THE CASE IN POSITION TO RECEIVE AIR MOVING FORWARDLY ANDDOWNWARDLY ADJACENT SAID ACCESS OPENING, REFRIGERATING MEANS WITHIN SAIDCASE, MEANS FOR CONDUCTING ONE PORTION OF THE AIR RECEIVED BY SAID DUCTMEANS TO SAID REFRIGERATING MEANS FOR RECIRCULATION THROUGH SAID DISPLAYSPACE, AND MEANS FOR DIRECTING ANOTHER PORTION OF THE AIR RECEIVED BYSAID DUCT MEANS TO THE EXTERIOR OF SAID DISPLAY SPACE.